Angle grinders are commonly used for grinding cement or other similar tasks. Without a dust shroud, debris is scattered over a wide area. It is desirable to contain the dust which is created for several reasons. It is desirable to contain the dust and debris to keep the workplace cleaner and to minimize the time necessary to clean up afterwards. While grinding cement, for example, fine dust is often created which spreads a large distance and can be quite difficult to clean up afterwards. It is also desirable to contain the dust and debris to keep the same from getting into the tool itself, causing premature failure of the bearings, motor, etc. Additionally, debris such as concrete dust poses a health risk to the machine operator and others who may breathe it. It is thus desirable to collect the dust to minimize any exposure to the dust.
Dust shrouds are often used to both contain grinding dust and prevent a mess as well as to protect an operator from debris and dust. Additionally, the dust shroud should protect the operator from contact with the grinding disc. These shrouds generally attach to an angle grinder between the grinder body and the grinding disc, typically to a cylindrical collar formed around the grinder output shaft. The shroud then forms a barrier between the operator and the grinding disc. The shroud often extends around the edges of the grinding disc, leaving the bottom grinding portion open for use. Thus, the dust shroud provides a dust and debris barrier and a safety barrier.
Many dust shrouds provide a vacuum port so that a vacuum may be used to suction dust and debris out of the shroud. This avoids airborne dust and debris that can lead to such health problems as silicosis. The use of a vacuum also keeps the workplace clean of debris, dramatically reducing the time necessary to clean up after a grinding job. Vacuum dust shrouds are commonly used while grinding concrete. It can be appreciated how, without a shroud, a significant amount of concrete dust is spread across a wide area. With a vacuum shroud, very little dust goes uncollected. The use of a vacuum shroud can also protect the tool by preventing dust and debris from entering the motor and gears, thus extending tool life.
Effective vacuum shrouds typically cover the top and entire perimeter of the grinding disc so that most of the dust and debris is captured by the vacuum and the disc is not exposed to the operator. Complete enclosure of the perimeter of the grinding disc, however, prevents the tool operator from grinding into a corner, such as when grinding the edge of a floor adjacent a wall. A dust shroud with an opening on a side of the shroud, while allowing grinding into such a corner, captures dust less effectively than a completely enclosed shroud. It is thus desirable to have a shroud with an opening while grinding into a corner and a completely enclosed shroud while during other times.
Vacuum shrouds for grinders have been made which allow a user to remove a hatch portion of the shroud from the rest of the shroud body to expose a side of the grinding disc and allow grinding into a corner. It has been found, however, that workers tend to remove the hatch to grind into a corner and often either lose the hatch or simply neglect to replace the hatch after finishing the corner. Workers will often leave the hatch off of the shroud to save the time required to remove and replace the hatch. A worker needs both hands for operating the grinder, and thus can not hold the hatch while grinding. It is thus not uncommon for workers to simply place the hatch in a toolbox or on the floor, and lose the hatch or simply not replace the hatch as is desired.
Some shrouds have been made with a hatch that is attached to the shroud with a hinge. The hatch folds open when desired. These hatches, however, do not stay open well. The hatches often close during use when the hatch catches on something in the workplace or simply closes due to the vibration of the grinder. These hatches thus become an inconvenience to the operator and may even pose a safety hazard if the hatch interferes with the use of the grinder.
The failure to replace the hatch when not grinding a corner is more detrimental than one might think. In addition to the danger of having an exposed grinding disc, having an opening in the perimeter of the dust shroud allows a significant portion of the grinding dust to escape and not be collected by the vacuum. The dust from grinding concrete is very fine, and will float in the air for a long period of time, allowing uncollected dust to settle over a large area. Additionally, the dust contains compounds from the concrete which are harmful to the lungs, and uncollected dust poses more of a health risk to the worker and to others.
Thus there is a need for a grinder dust shroud with a corner grinding hatch which better encourages workers to use the hatch. There is a need for a grinder dust shroud with an access hatch which is attached to the shroud itself so that the hatch can not be removed from the shroud and lost. There is a need for a hatch design which is easily opened and closed while still remaining effective in capturing dust and while still protecting a worker from the grinding disc and the grinding debris.